In typewriters having the ability to position the print point at any of several different positions within a normal escapement pattern, such as for example, in those using a conventional lead screw type of escapement arrangement, it is possible to either intentionally or inadvertently create misalignment with the normal escapement pattern. A lead screw escapement arrangement is commonly used since such a system is conducive to the implementation of proportional spacing. Particularly in proportional spacing typewriters, it is difficult to reposition the print point over a previously printed character because of variances in character width. This repositioning can also be difficult where the print point at some point in the line has been misaligned either intentionally or inadvertently such as for example where a character has been squeezed in or where characters have been removed and then subsequent printed characters have been expanded to fill the space. In situations such as that immediately described above it is difficult to realign the print point with those positions for the removal and correction of erroneously typed characters. When the operator attempts to align the character it is dependent upon the operator's ability to visualize intersections of guide marks with edges or centers of characters and this does not lead to accurate reliable positioning. Thus when the operator attempts to remove the character from the page by erasure through the use of the corrections mechanism on such a typewriter the characters are not properly aligned and either ghost images remain on the paper or repetitive corrections at small escapement increments are necessary, thus thereby potentially tearing the page.
On some typewriters it has been necessary to provide an extendable guide member which may be extended into the print point area to facilitate repositioning. This member must of necessity be retractable in order to not interfere with subsequent printing operations. Other solutions have included guide marks on the card holder or other reference marks which the operator must observe and attempt to align with the desired print position. Due to the necessity for clearance between the impacting print element and the card holder or other structure in that area, it is many times necessary to displace these reference marks by some distance from the actual print point thereby increasing the possibility for misjudgments. This is particularly true where the typewriter is capable of positioning the print carriage in very small increments of a full escapement increment.
It is therefore, an object of this invention to facilitate the alignment of the print point of the typewriter with a desired location on the printed page.
It is an additional object of this invention to ease the operator's burden in relocating the print point over a desired position on a printed page.
It is an additional object of this invention to electronically move the carriage from a preliminary alignment position to a final alignment position thereby insuring accurate relocation of the print point over a particular position on a page.